Using a genetic risk score to calculate the optimal age for an individual to undergo coronary artery calcium screening

Polygenic risk score in comparison with C-reactive protein for predicting incident coronary heart disease

BACKGROUND AND AIMS

Despite interest in the use of polygenic risk scores (PRS) for predicting coronary heart disease (CHD) risk, the clinical utility of PRS compared to conventional risk factors has not been demonstrated. We compared the performance of PRS with that of high-sensitivity C-reactive protein (hsCRP) in two well-established cohorts.

METHODS

The study population included individuals of European ancestry free of baseline CHD from ARIC (N = 13,113) and the Framingham Offspring Study (FHS) (N = 2,696). The primary predictors included a validated PRS consisting of >6.6 million single nucleotide polymorphisms and hsCRP. The outcome was incident CHD, defined as non-fatal or fatal myocardial infarction. We compared the performance of both predictors after adjusting for the Pooled Cohort Equations in multivariable-adjusted Cox regression models. We assessed discrimination and reclassification using c-statistics and net reclassification improvement.

RESULTS

Incident CHD occurred in 565 ARIC and 153 FHS participants. In multivariable-adjusted models, both PRS and hsCRP were associated with incident CHD (p < 0.05 in both cohorts). In models incorporating both predictors, strengths of association were similar. For instance, in ARIC, the hazard ratio per SD increment was 1.38 (95% CI, 1.27-1.50, p = 2.94 × 10-14) for PRS and 1.41 (1.30-1.55, p = 3.10 × 10-15) for hsCRP. Neither predictor significantly increased model discrimination or net reclassification when compared with models containing the Pooled Cohort Equations alone.

CONCLUSIONS

In two independent cohorts, PRS performed similarly to hsCRP for the prediction of CHD risk. These findings suggest PRS does not have unique clinical utility beyond this widely-available, inexpensive measure of risk in unselected middle-aged populations.

Genomic Innovation in Early Life Cardiovascular Disease Prevention and Treatment

Cardiovascular disease (CVD) is a leading cause of morbidity and mortality globally. Although CVD events do not typically manifest until older adulthood, CVD develops gradually across the life-course, beginning with the elevation of risk factors observed as early as childhood or adolescence and the emergence of subclinical disease that can occur in young adulthood or midlife. Genomic background, which is determined at zygote formation, is among the earliest risk factors for CVD. With major advances in molecular technology, including the emergence of gene-editing techniques, along with deep whole-genome sequencing and high-throughput array-based genotyping, scientists now have the opportunity to not only discover genomic mechanisms underlying CVD but use this knowledge for the life-course prevention and treatment of these conditions. The current review focuses on innovations in the field of genomics and their applications to monogenic and polygenic CVD prevention and treatment. With respect to monogenic CVD, we discuss how the emergence of whole-genome sequencing technology has accelerated the discovery of disease-causing variants, allowing comprehensive screening and early, aggressive CVD mitigation strategies in patients and their families. We further describe advances in gene editing technology, which might soon make possible cures for CVD conditions once thought untreatable. In relation to polygenic CVD, we focus on recent innovations that leverage findings of genome-wide association studies to identify druggable gene targets and develop predictive genomic models of disease, which are already facilitating breakthroughs in the life-course treatment and prevention of CVD. Gaps in current research and future directions of genomics studies are also discussed. In aggregate, we hope to underline the value of leveraging genomics and broader multiomics information for characterizing CVD conditions, work which promises to expand precision approaches for the life-course prevention and treatment of CVD.

Polygenic Risk Scores for Prediction of Subclinical Coronary Artery Disease in Persons With Human Immunodeficiency Virus (HIV): The Swiss HIV Cohort Study

BACKGROUND

In people with human immunodeficiency virus (HIV) (PWH), individual polygenic risk scores (PRSs) are associated with coronary artery disease (CAD) events. Whether PRSs are associated with subclinical CAD is unknown.

METHODS

In Swiss HIV Cohort Study participants of European descent, we defined subclinical CAD as presence of soft, mixed, or high-risk plaque (SMHRP) on coronary computed tomography (CT) angiography, or as participants in the top tertile of the study population's coronary artery calcium (CAC) score, using noncontrast CT. We obtained univariable and multivariable odds ratios (ORs) for subclinical CAD endpoints based on nongenetic risk factors, and validated genome-wide PRSs built from single nucleotide polymorphisms associated with CAD, carotid intima-media thickness (IMT), or longevity in the general population.

RESULTS

We included 345 genotyped participants (median age, 53 years; 89% male; 96% suppressed HIV RNA); 172 and 127 participants had SMHRP and CAC, respectively. CAD-associated PRS and IMT-associated PRS were associated with SMHRP and CAC (all P < .01), but longevity PRS was not. Participants with unfavorable CAD-PRS (top quintile) had an adjusted SMHRP OR = 2.58 (95% confidence interval [CI], 1.18-5.67), and a CAC OR = 3.95 (95% CI, 1.45-10.77) vs. bottom quintile. Unfavorable nongenetic risk (top vs. bottom quintile) was associated with adjusted SMHRP OR = 24.01 (95% CI, 9.75-59.11), and a CAC-OR = 65.07 (95% CI, 18.48-229.15). Area under the receiver operating characteristic curve increased when we added CAD-PRS to nongenetic risk factors (SMHRP: 0.75 and 0.78, respectively; CAC: 0.80 and 0.83, respectively).

CONCLUSIONS

In Swiss PWH, subclinical CAD is independently associated with an individual CAD-associated PRS. Combining nongenetic and genetic cardiovascular risk factors provided the most powerful subclinical CAD prediction.

Molecular Mechanisms of Vascular Health: Insights From Vascular Aging and Calcification

Cardiovascular disease is the most common cause of death worldwide, especially beyond the age of 65 years, with the vast majority of morbidity and mortality due to myocardial infarction and stroke. Vascular pathology stems from a combination of genetic risk, environmental factors, and the biologic changes associated with aging. The pathogenesis underlying the development of vascular aging, and vascular calcification with aging, in particular, is still not fully understood. Accumulating data suggests that genetic risk, likely compounded by epigenetic modifications, environmental factors, including diabetes and chronic kidney disease, and the plasticity of vascular smooth muscle cells to acquire an osteogenic phenotype are major determinants of age-associated vascular calcification. Understanding the molecular mechanisms underlying genetic and modifiable risk factors in regulating age-associated vascular pathology may inspire strategies to promote healthy vascular aging. This article summarizes current knowledge of concepts and mechanisms of age-associated vascular disease, with an emphasis on vascular calcification.

Relationship Between Cardio-Ankle Vascular Index And Coronary Artery Calcification In A Population Sample Of Southwestern Siberia

Objective — To examine associations between cardio-ankle vascular index (CAVI) and coronary artery calcium (CAC) score a population sample of southwestern Siberia. Methods — From the sample of 1,620 people the final analysis included 1,316 participants 25 to 64 years of age who were enrolled in an observational cross-sectional study, Epidemiology of Cardiovascular Diseases and Their Risk Factors in the Russian Federation (ESSE-RF). Study participants were split among two groups: Group 1 with CAVI≥9.0 (n=128) and Group 2 with CAVI<9.0 (n=1,188). Prevalence of coronary artery calcification in both groups was analyzed via the Agatston method. We compared main demographic and clinical data between the groups, as well as CAC scores. Results — Elevated CAVI (≥9.0) was present in 9.7% of people included in a population sample from southwestern Siberia, and coronary artery calcification was found in 33.5% of the sample. While similar rates of minimum, mild, moderate and severe CAC score were observed in the participants with elevated and normal CAVI values, CAVI as a continuous variable was statistically significantly associated with moderate and severe CAC scores (OR 1.20, 95% CI 1.06-1.37, p=0.004). CAC score values were higher in individuals at the age of ≥50 years with pathological CAVI values (116±489 vs. 75±425 in normal CAVI, p=0.035), but not in patients under the age of 50 years (64±227 and 85±475, p=0.343). Conclusion — CAVI could possibly be used as a feasible marker before assessing the CAC score in some asymptomatic Caucasian subjects, but identifying the most appropriate methods and participants, whom it could be clearly applicable to, requires further studying.

Association of polygenic risk scores with incident atherosclerotic cardiovascular disease events among individuals with coronary artery calcium score of zero: The multi-ethnic study of atherosclerosis

BACKGROUND

Polygenic risk scores (PRS) are associated with atherosclerotic cardiovascular disease (ASCVD) events. We studied incident ASCVD among individuals with absent coronary artery calcium (CAC = 0), to investigate the association of PRS with incident ASCVD among such individuals.

METHODS

Data was used from Multi-Ethnic Study of Atherosclerosis (MESA), a prospective cohort study of participants free of clinical CVD at baseline. PRS were developed based on a literature-derived list of single-nucleotide polymorphisms (SNPs) weighted by effect size. The coronary heart disease (CHD) PRS contained 180 SNPs, and the stroke PRS had 32 SNPs. These SNPs were combined to compute an ASCVD PRS. The PRS were calculated among 3132 participants with CAC = 0. Multivariable-adjusted Cox proportional hazards models evaluated the association between each PRS (top 20% vs bottom 50%) and ASCVD.

RESULTS

The study population included 3132 individuals with CAC = 0 [mean (SD) age 58 (9) years; 63% female, 33% White, 31% Black, 12% Chinese-American, 24% Hispanic]. Over a median follow-up of 16 years, there were 108 incident CHD events and 93 stroke events. ASCVD event rates were generally <7.5 per 1000-person years for all ASCVD events regardless of PRS risk stratum. The ASCVD PRS was significantly associated with incident ASCVD: (HR; 95% CI) (1.63; 1.11, 2.39). The CHD PRS was not associated with any ASCVD outcome, whereas the stroke PRS was significantly associated with ASCVD (1.84; 1.27, 2.68), CHD (1.79; 1.05, 3.06), and stroke (1.96; 1.19, 3.23). The stroke PRS results were significant among women and non-Whites.

CONCLUSIONS

Among individuals with CAC = 0, the ASCVD PRS was associated with incident ASCVD events. This appears to be driven by genetic variants related to stroke but not CHD, and particularly among women and non-Whites. ASCVD event rates remained below the threshold recommended for consideration for initiation of statin therapy even in the high PRS groups.

New Cardiovascular Risk Assessment Techniques for Primary Prevention: JACC Review Topic of the Week

Risk factor-based models fail to accurately estimate risk in select populations, in particular younger individuals. A sizable number of people are also classified as being at intermediate risk, for whom the optimal preventive strategy could be more precise. Several personalized risk prediction tools, including coronary artery calcium scoring, polygenic risk scores, and metabolic risk scores may be able to improve risk assessment, pending supportive outcome data from clinical trials. Other tools may well emerge in the near future. A multidimensional approach to risk prediction holds the promise of precise risk prediction. This could allow for targeted prevention minimizing unnecessary costs and risks while maximizing benefits. High-risk individuals could also be identified early in life, creating opportunities to arrest the development of nascent coronary atherosclerosis and prevent future clinical events.

Polygenic Risk Score to Identify Subclinical Coronary Heart Disease Risk in Young Adults

BACKGROUND

Polygenic risk scores (PRS) may enhance risk stratification for coronary heart disease among young adults. Whether a coronary heart disease PRS improves prediction beyond modifiable risk factors in this population is not known.

METHODS

Genotyped adults aged 18 to 35 years were selected from the CARDIA study (Coronary Artery Risk Development in Young Adults; n=1132) and FOS (Framingham Offspring Study; n=663). Systolic blood pressure, total and HDL (high-density lipoprotein) cholesterol, triglycerides, smoking, and waist circumference or body mass index were measured at the visit 1 exam of each study, and coronary artery calcium, a measure of coronary atherosclerosis, was assessed at year 15 (CARDIA) or year 30 (FOS). A previously validated PRS for coronary heart disease was computed for each subject. The C statistic and integrated discrimination improvement were used to compare improvements in prediction of elevated coronary artery calcium between models containing the PRS, risk factors, or both.

RESULTS

There were 62 (5%) and 93 (14%) participants with a coronary artery calcium score >20 (CARDIA) and >300 (FOS), respectively. At these thresholds, the C statistic changes of adding the PRS to a risk factor-based model were 0.015 (0.004-0.028) and 0.020 (0.001-0.039) in CARDIA and FOS, respectively. When adding risk factors to a PRS-based model, the respective changes were 0.070 (0.033-0.109) and 0.051 (0.017-0.079). The integrated discrimination improvement, when adding the PRS to a risk factor model, was 0.027 (-0.006 to 0.054) in CARDIA and 0.039 (0.0005-0.072) in FOS.

CONCLUSIONS

Among young adults, a PRS improved model discrimination for coronary atherosclerosis, but improvements were smaller than those associated with modifiable risk factors.

Monogenic and Polygenic Models of Coronary Artery Disease

PURPOSE OF THE REVIEW

Coronary artery disease (CAD) is a common disease globally attributable to the interplay of complex genetic and lifestyle factors. Here, we review how genomic sequencing advances have broadened the fundamental understanding of the monogenic and polygenic contributions to CAD and how these insights can be utilized, in part by creating polygenic risk estimates, for improved disease risk stratification at the individual patient level.

RECENT FINDINGS

Initial studies linking premature CAD with rare familial cases of elevated blood lipids highlighted high-risk monogenic contributions, predominantly presenting as familial hypercholesterolemia (FH). More commonly CAD genetic risk is a function of multiple, higher frequency variants each imparting lower magnitude of risk, which can be combined to form polygenic risk scores (PRS) conveying significant risk to individuals at the extremes. However, gaps remain in clinical validation of PRSs, most notably in non-European populations. With improved and more broadly utilized genomic sequencing technologies, the genetic underpinnings of coronary artery disease are being unraveled. As a result, polygenic risk estimation is poised to become a widely used and powerful tool in the clinical setting. While the use of PRSs to augment current clinical risk stratification for optimization of cardiovascular disease risk by lifestyle change or therapeutic targeting is promising, we await adequately powered, prospective studies, demonstrating the clinical utility of polygenic risk estimation in practice.

Polygenic Risk Scores to Identify CVD Risk and Tailor Therapy: Hope or Hype?

PURPOSE OF REVIEW

The purpose of this review is to understand the conceptual basis and implications of polygenic risk scores (PRS) in assessing risk of future coronary artery disease (CAD).

RECENT FINDINGS

Genetic information from the USA and beyond has been pooled together to create population-based biobanks, composed of millions of genotyped individuals, which have helped further our understanding of the relationship between single nucleotide polymorphisms (SNPs) and CAD. Contemporary PRS composed of millions of SNPs now serve as the gold standard and have been evaluated in several cohort studies to predict risk of CAD and potentially help guide pharmacotherapy. The development of PRS has enhanced our understanding of the relationship between genes and disease, thereby facilitating CAD risk prediction. While certain constraints currently limit their utility in clinical practice, further refinement of this tool will enable clinicians to more fully understand genetic risk and improve preventive care.

Polygenic risk scores: how much do they add?

PURPOSE OF REVIEW

Current methods to assess genetic risk of familial hypercholesterolemia and coronary artery disease (CAD) focus on testing monogenic mutations in well known genes. Here we review recent developments in polygenic risk scores (PRSs) for LDL cholesterol and for CAD, and how they may add to current risk prediction algorithms.

RECENT FINDINGS

PRSs can identify 10-20 times as many individuals at high polygenic risk compared with monogenic mutations, and PRSs can modulate the effect of a monogenic variant on risk. Current risk factor prediction tools for prevention of CAD incompletely capture polygenic susceptibility, and PRSs may identify subgroups of patients who are likely to benefit more from lipid-lowering therapy. Finally, PRSs can be quantified already at birth, long before other risk factors used to predict CAD, and before clinical manifestations of disease.

SUMMARY

PRSs for CAD may soon be incorporated into clinical practice. Therefore, there is an urgent need to establish both analytical and clinical reporting standards for PRSs, and for validating scores in different ethnicities. Thresholds for intervention need to be established for PRSs and integrated into established risk scores. Training programs are needed for clinical staff to learn to communicate polygenic risk in a comprehensive way to the patient.

Genetic Risk Assessment for Atherosclerotic Cardiovascular Disease: A Guide for the General Cardiologist

Genetic testing for cardiovascular (CV) disease has had a profound impact on the diagnosis and evaluation of monogenic causes of CV disease, such as hypertrophic and familial cardiomyopathies, long QT syndrome, and familial hypercholesterolemia (FH). The success in genetic testing for monogenic diseases has prompted special interest in utilizing genetic information in the risk assessment of more common diseases such as atherosclerotic cardiovascular disease (ASCVD). Polygenic risk scores (PRS) have been developed to assess the risk of coronary artery disease (CAD) that now include millions of single-nucleotide polymorphisms (SNPs) that have been identified through genome-wide association studies (GWAS). While these PRS have demonstrated a strong association with CAD in large cross-sectional population studies, there remains intense debate regarding the added value that PRS contribute to existing clinical risk prediction models such as the pooled cohort equations (PCEs). In this review, we provide a brief background of genetic testing for monogenic drivers of CV disease and then focus on the recent developments in genetic risk assessment of ASCVD, including the use of PRS. We outline the genetic testing that is currently available to all cardiologists in the clinic and discuss the evolving sphere of specialized cardiovascular genetics programs (CVGPs) that integrate the expertise of cardiologists, geneticists, and genetic counselors. Finally, we review the possible implications that PRS and pharmacogenomic data may soon have on clinical practice in the care for patients with or at risk of developing ASCVD.

Targeted Coronary Artery Calcium Screening in High-Risk Younger Individuals Using Consumer Genetic Screening Results

OBJECTIVES

The goal of this study was to assess the utility of a genetic risk score (GRS) in targeted coronary artery calcium (CAC) screening among young individuals.

BACKGROUND

Early CAC screening and preventive therapy may reduce long-term risk of a coronary heart disease (CHD) event. However, identifying younger individuals at increased risk remains a challenge. GRS for CHD are age independent and can stratify individuals on various risk trajectories.

METHODS

Using 142 variants associated with CHD events, we calculated a GRS in 1,927 individuals in the CARDIA (Coronary Artery Risk Development in Young Adults) cohort (aged 32 to 47 years) and 6,600 individuals in the MESA (Multi-Ethnic Study of Atherosclerosis) cohort (aged 44 to 87 years). We assessed GRS utility to predict CAC presence in the CARDIA cohort and stratify individuals of varying risk for CAC presence over the lifetime in both cohorts.

RESULTS

The GRS predicted CAC presence in CARDIA males. It was not predictive in CARDIA females, which had a CAC prevalence of 6.4%. In combined analysis of the CARDIA and MESA cohorts, the GRS was predictive of CAC in both males and females and was used to derive an equation for the age at which CAC probability crossed a predetermined threshold. When assessed in combination with traditional risk factors, the GRS further stratified individuals. For individuals with an equal number of traditional risk factors, probability of CAC reached 25% approximately 10 years earlier for those in the highest GRS quintile compared to the lowest.

CONCLUSIONS

The GRS may be used to target high-risk younger individuals for early CAC screening.

A multi-omics view of the complex mechanism of vascular calcification

Vascular calcification is a high incidence and high risk disease with increasing morbidity and high mortality, which is considered the consequence of smooth muscle cell transdifferentiation initiating the mechanism of accumulation of hydroxyl calcium phosphate. Vascular calcification is also thought to be strongly associated with poor outcomes in diabetes and chronic kidney disease. Numerous studies have been accomplished; however, the specific mechanism of the disease remains unclear. Development of the genome project enhanced the understanding of life science and has entered the post-genomic era resulting in a variety of omics techniques used in studies and a large amount of available data; thus, a new perspective on data analysis has been revealed. Omics has a broader perspective and is thus advantageous over a single pathway analysis in the study of complex vascular calcification mechanisms. This paper reviews in detail various omics studies including genomics, proteomics, transcriptomics, metabolomics and multiple group studies on vascular calcification. Advances and deficiencies in the use of omics to study vascular calcification are presented in a comprehensive view. We also review the methodology of the omics studies and omics data analysis and processing. In addition, the methodology and data processing presented here can be applied to other areas. An omics landscape perspective across the boundaries between genomics, transcriptomics, proteomics and metabolomics is used to examine the mechanisms of vascular calcification. The perspective combined with various technologies also provides a direction for the subsequent exploration of clinical significance.

Genetic Risk Score for Coronary Heart Disease: Review

The present review deals with the stages of creation, methods of calculation, and the use of a genetic risk score for coronary heart disease in various populations. The concept of risk factors is generally recognized on the basis of the results of epidemiological studies in the 20th century; according to this concept, the high prevalence of diseases of the circulatory system is due to lifestyle characteristics and associated risk factors. An important and relevant task for the healthcare system is to identify the population segments most susceptible to cardiovascular diseases (CVDs). The level of individual risk of an unfavorable cardiovascular prognosis is determined by genetic factors in addition to lifestyle factors.

Premature Atherosclerotic Cardiovascular Disease: What Have We Learned Recently?

PURPOSE OF REVIEW

In contrast to patients with non-premature atherosclerotic cardiovascular disease (ASCVD), patients with premature ASCVD have not observed a similar decline in cardiovascular mortality and recurrent adverse events. We sought to review the underlying risk factors, potential gaps in medical management, associated outcomes, and tools for risk prognostication among patients with premature ASCVD.

RECENT FINDINGS

In addition to traditional cardiovascular risk factors (i.e., diabetes, familial hypercholesterolemia), non-traditional risk factors such as chronic inflammatory conditions, recreational drug use, genetics, and pregnancy-related complications play a key role in development and progression of premature ASCVD. Patients with premature ASCVD, and especially women, receive less optimal medical management as compared to their non-premature counterparts. There is an increasing prevalence of cardiovascular risk factors among young adults. Hence, this population remains at an elevated risk for premature ASCVD and subsequent adverse cardiovascular events. Future studies evaluating different risk assessment tools and focusing on young patients across all three major domains of ASCVD are needed.

Polygenic Scores to Assess Atherosclerotic Cardiovascular Disease Risk: Clinical Perspectives and Basic Implications

An individual's susceptibility to atherosclerotic cardiovascular disease is influenced by numerous clinical and lifestyle factors, motivating the multifaceted approaches currently endorsed for primary and secondary cardiovascular disease prevention. With growing knowledge of the genetic basis of atherosclerotic cardiovascular disease-in particular, coronary artery disease-and its contribution to disease pathogenesis, there is increased interest in understanding the potential clinical utility of a genetic predictor that might further refine the assessment and management of atherosclerotic cardiovascular disease risk. Rapid scientific and technological advances have enabled widespread genotyping efforts and dynamic research in the field of coronary artery disease genetic risk prediction. In this review, we describe how genomic analyses of coronary artery disease have been leveraged to create polygenic risk scores. We then discuss evaluations of the clinical utility of these scores, pertinent mechanistic insights gleaned, and practical considerations relevant to the implementation of polygenic risk scores in the health care setting.

An age-matched computed tomography angiographic study of coronary atherosclerotic plaques in patients with familial hypercholesterolaemia

BACKGROUND AND AIMS

Familial hypercholesterolaemia (FH) is characterised by a high, but variable risk of premature coronary artery disease (CAD). Cardiac computed tomography angiography (CCTA) can be employed to assess subclinical coronary atherosclerosis. We investigated the features and distribution of coronary artery plaques in asymptomatic patients with and without genetically confirmed heterozygous FH.

METHODS

We undertook an aged-matched case-control study of asymptomatic phenotypic FH patients with (cases, M+) and without (controls, M-) an FH-causing mutation. Coronary atherosclerosis was assessed by CCTA and calcium scoring. Coronary segments were evaluated for global and vessel-level coronary plaques and degree of stenosis.

RESULTS

We studied 104 cases and 104 controls (mean age 49.9 ± 10.4 years), who had a similar spectrum of non-cardiovascular risk factors. Pre-treatment plasma LDL-cholesterol was higher in the M+ than M- group (7.8 ± 2.1 vs 6.2 ± 1.2 mmol/L, p<0.001). There was a greater proportion of patients with mixed and calcified plaque, as well as a higher coronary artery calcium score and segment stenosis score (all p<0.05), in the M+ compared with the M- group. M+ patients also had a significantly higher frequency of coronary artery calcium in the left main and anterior descending and right coronary arteries (all p<0.05), but not in the left circumflex.

CONCLUSIONS

Among patients with phenotypic FH, those with a genetically confirmed diagnosis had a higher frequency and severity of coronary atherosclerotic plaques, and specifically more advanced calcified plaques.

Polygenic Risk Scores in Coronary Artery Disease and Atrial Fibrillation

Coronary artery disease (CAD) and atrial fibrillation (AF) are two highly prevalent cardiovascular disorders that are associated with substantial morbidity and mortality. Conventional clinical risk factors for these disorders may not be identified prior to mid-adult life when pathophysiological processes are already established. A better understanding of the genetic underpinnings of disease should facilitate early detection of individuals at risk and preventative intervention. Single rare variants of large effect size that are causative for CAD, AF, or predisposing factors such as hypertension or hyperlipidaemia, may give rise to familial forms of disease. However, in most individuals, CAD and AF are complex traits in which combinations of genetic and acquired factors play a role. Common genetic variants that affect disease susceptibility have been identified by genome-wide association studies, but the predictive value of any single variant is limited. To address this issue, polygenic risk scores (PRS), comprised of suites of disease-associated common variants have been devised. In CAD and AF, incorporation of PRS into risk stratification algorithms has provided incremental prognostic information to clinical factors alone. The long-term health and economic benefits of PRS-guided clinical management remain to be determined however, and further evidence-based data are required.